# A060581 (b-file synthesized from sequence entry)
0 1
1 15
2 81
3 441
4 2151
5 9957
6 43122
7 174162
8 666267
9 2403987
10 8183601
11 26281065
12 79660856
13 228180456
14 618992466
15 1595081266
16 3918506466
17 9211519476
18 20797923546
19 45258309066
20 95225448306
21 194283668576
22 385361919996